1. Short for coder/decoder. Hardware that can convert audio or video signals between analog and digital forms.
2. Short for compressor/decompressor. Hardware or software that can compress and uncompress audio or video data. See also compress2, uncompress.
3. Hardware that combines the functions of definitions 1 and 2.
An abbreviation for Coder-Decoder. An analog-to-digital (A/D) and digital-to-analog (D/A) converter for translating the signals from the outside world to digital, and back again.